Last night our Star Gazing subject of the week, Penn Badgley attended the premiere of his new thriller, "The Stepfather" (out Friday), and boy did Lonely Boy look dapper!

Wearing Calvin Klein, Penn joked that he chose the label because he wears their undies. The Gossip Boy's "Stepfather" costar, Amber Heard, meanwhile didn't choose a designer known for under garments — she went with vintage Oscar de la Renta. Do yourself a fashion favor and check out how gorgeous the duo looked on the red carpet by pressing play below. Then check out our photo flipbook to see who else showed up to support the cast. (Most notable, Penn's girl, Blake Lively!)